1. Field of the Invention
This invention relates to powders of plant green juice. More specifically, the invention relates to powders of plant green juice having an improved tastiness which are storable for long and a process for their production.
2. Description of the Related Art
If drying green leaves of any plant usually, this involves such phenomenon that generally the leaves are discolored into yellow or turn brown, etc. Further, it is well known that even if the leaves keep their green color for a short period of time after the production of powders, its dried product loses a green color during storage and involves a change such as browning, degeneration or a change in smell.
The Inventors have hitherto made research works on the powderization of a plant green juice obtained by squeezing any plant having green leaves, its stabilization, its long-term storage method, etc. Its outcomes are reported in a process for producing powders of plant green juice taste having an improved drinkability (Japanese Patent Publication No. 46-36177), a process for producing powders of green leaves of barley and wheat (Japanese Patent Publication No. 46-38548), a process for producing powders of plant green juice (Japanese Patent Publication No. 46-41177) and other numerous scientific literatures.
The green color of green leaves and green plants is chlorophyll. It is also known that chlorophyll is converted into colorless phaeophytin by suffering from an action of ultraviolet rays, an acid, an enzyme (chlorophyllase), etc., in consequence of which a brown color and a red color of xanthophyll, carotenoid, flavonoid pigment and the like become notable.
In the above Japanese Patent Publn. No. 46-38548, etc. the Inventors have proposed a process for producing powders of plant green juice which are free from any unpleasant smell and which may be stored stably for a long period of time by adjusting the pH of the plant green juice obtainable by mechanicallly squeezing green leaves of barley and wheat or green plants to form plant green juice, adjusting the pH of the green juice to be 6-9, with an alkaline substance such as carbonate, bicarbonate or hydroxide of an alkali metal or an alkaline earth metal like sodium carbonate, potassium carbonate, sodium bicarbonate, caustic potash, ammonium hydroxide or magnesium hydroxide and then spray drying or lyophilizing the obtained green juice.
The powders of the plant green juice produced by the above proposed processes can be stored for a relatively long period of time, usually one to two years without causing the green color of the raw green juice to discolor or fade. However, nobody could settle defects as foodstuffs that acid components (various organic acids and an amino acid) contained in the green juice were neutralized by adding the above alkaline substance, thereby to cause a change in the inherent flavor of the green juice in combination with the taste of said alkaline substance per se and to degrade the tastiness of powders of the green juice. Moreover, it has been clarified by subsequent long-term research works that at the time of adding the above alkaline substance the following phenomena are promoted thereby to darken a green color of the green juice and degrade the brightness of a fresh, vivid green color inherent to the juice, i.e. alkali metal chlorination or alkaline earth metal chlorination of chlorophyll contained in the green juice, saponification of fatty acid ester, reddish browning of flavonoid type pigments, etc.